A digital twin is never only a technical replica. It is a political address system. It speaks to engineers, planners, software, sensors, administrations, interfaces, citizens, vehicles and models at once. DualAddress names this condition: the need for urban knowledge to communicate simultaneously with human subjects and machine systems without collapsing one into the other. This reader studies inclusive mobility, digital twins and urban belonging as one field because movement in the contemporary city is increasingly mediated by models, but belonging is still lived through bodies, memories, attachments and unequal access. The European debate on inclusive and sustainable urban mobility provides the first frame. Mobility can no longer be treated as a narrow transport-sector problem. It is ecological, social, digital, spatial and institutional. Electrification, autonomous vehicles, logistics systems, artificial intelligence and connectivity must be read alongside children, older people, disabled users, transport poverty, public participation and municipal capacity. The future of mobility is not simply a future of cleaner or smarter movement. It is a future of differentiated access.

Digital twin research brings this problem into technical focus. Li and colleagues’ concept of Digital Twin Federation is especially useful because it refuses the fantasy of one total urban model. Mobility systems are distributed across infrastructures, platforms, behaviours, sensors, institutions and temporal scales. Their twins must be federated rather than monolithic. The inclusion of human-in-the-loop architecture is crucial. It recognises that urban mobility cannot be governed by automated representation alone. Stakeholder judgment, behavioural uncertainty and public deliberation must remain inside the model. Nag and colleagues’ review of transport digital twins sharpens this through classification. Many systems described as digital twins are actually digital models or digital shadows. A model represents. A shadow receives data. A twin requires interaction, connection, service and feedback. HybridLegibility becomes relevant here because the urban twin must be legible to both technical systems and public actors. If a twin can be understood only by specialists, it risks becoming another opaque instrument of governance. If it is simplified only for public display, it may become symbolic theatre. The challenge is hybrid readability.

Belonging complicates the digital frame. Urban mobility is never simply the ability to move. It is the ability to remain connected to meaningful places, relationships and routines. Willcocks-Musselman and colleagues’ work on place attachment and managed retreat shows that relocation, climate adaptation and movement involve identity, affect, continuity and loss. Pinkster and Loomans’ account of urban belonging as place-based affect extends this to everyday city life. Belonging is made through repeated encounters, social recognition, atmosphere, memory and the ordinary permission to inhabit.

PublicSyntax, as secondary operator, names the shared grammar required for mobility systems to become civic. A city’s mobility language cannot remain trapped in technical indicators. It must translate accessibility, waiting time, service gaps, transport poverty, digital exclusion, safety, care journeys and attachment into terms that can be publicly debated. Sustainable Urban Mobility Plans are important because they try to make mobility procedural: diagnosis, vision, indicators, measures, implementation, monitoring and review become part of one public cycle. This is not glamorous, but it is structurally important. Civic mobility depends on procedure as much as innovation. Smart-city inclusion research warns against rhetorical inclusion. Kolotouchkina, Ripoll González and Belabas show that smart cities often reproduce inequalities through digital access, literacy, age, disability and institutional participation gaps. UN-Habitat’s smart-city outlook similarly reorients smartness toward public value, human rights, standards, governance and ethical data infrastructures. Inclusion is not an added chapter after technical deployment. It must shape the architecture of the system. SitePaper, as secondary operator, connects this back to Socioplastics. A site is not only a physical location; it can also be a document with coordinates, a text that situates a problem, a paper that anchors a field. Digital twins often fail because they abstract place into system performance. SitePaper insists that every model must remain attached to situated evidence. A mobility twin must know where it stands: which city, which climate, which population, which institutional capacity, which histories of exclusion.

For Socioplastics, DualAddress also describes the corpus itself. At 6K, the field is written for human readers and machine systems. It is public text and technical trace, essay and index, archive and signal. This reader therefore acts as a mirror. A digital twin of mobility and a distributed textual corpus share the same problem: how to become legible across systems without losing embodied complexity. The answer is not to reject modelling. The answer is to make modelling accountable to belonging.

Bibliography

Expert Group on Urban Mobility (2025) Inclusive and Sustainable Future of Urban Mobility in Europe. Final version adopted by the EGUM Plenary, 30 January 2025. Brussels: European Commission.

Li, J., Grübel, J., Nadi, A., Snelder, M., van Arem, B. and Gao, J. (2026) ‘Digital twin federation for urban mobility assessment: Definition, pillars, and a human-in-the-loop functional architecture’, Transportation Research Part A: Policy and Practice, 211, 105086.

Nag, D., Brandel-Tanis, F., Pramestri, Z.A., Pitera, K. and Frøyen, Y.K. (2025) ‘Exploring digital twins for transport planning: a review’, European Transport Research Review, 17, 15.

Kolotouchkina, O., Ripoll González, L. and Belabas, W. (2024) ‘Smart cities, digital inequalities, and the challenge of inclusion’, Smart Cities, 7(6), pp. 3355–3370.

Rupprecht Consult – Forschung & Beratung GmbH (ed.) (2026) Guidelines for Developing and Implementing a Sustainable Urban Mobility Plan. Third edition. Cologne: Rupprecht Consult / EU Urban Mobility Observatory / European Commission.

Unger, N., Noka, V., Meyer, J., Cludius, J. and Kreye, K. (2026) Access Denied: Transport Poverty in Europe. Berlin: Oeko-Institut e.V. for Greenpeace CEE.

UN-Habitat (2024) World Smart Cities Outlook 2024. Nairobi: United Nations Human Settlements Programme.

Willcocks-Musselman, R., Baird, J., Foster, K., Woodhall-Melnik, J. and Sherren, K. (2025) ‘Finding mobility in place attachment research: lessons for managed retreat’, Frontiers in Climate, 7, article 1514408.

Pinkster, F.M. and Loomans, D. (2024) ‘Urban belonging as place-based affect’, Social & Cultural Geography.